家庭内唾液幽门螺杆菌感染的致病菌型分析

Genotypes analysis of Helicobacter pylori pathogenesis in the saliva

目的通过对家庭内(父、母、子)唾液幽门螺杆菌(Helicobacter pylori HP)的细菌菌型的分析,了解HP致病菌株在家庭内唾液中的感染传播情况。方法利用聚合酶链反应(Polymerase chain reaction PCR)的方法,对20个已知HP感染家庭(父、母、子)的60份唾液标本进行致病菌株(含cagA、vacAm1、vacAm2、vacAs1基因)的分布检测,用χ2检验和确切概率法对检测结果进行统计学处理分析。结果①家庭内同时感染同类型致病基因型的家庭有14个,其中同时感染cagA与vacAs1基因亚型的家庭有5个,感染cagA与vacAm2基因亚型的家庭有4个,感染vacAm1与vacAm2基因亚型的家庭有3个,只感染一种基因亚型的家庭有2个;其余6个家庭HP感染基因型不完全一致。②含cagA、vacAm1、vacAm2、vacAs1基因的HP致病菌在成人与儿童的阳性检测率为45%(27/40),55%(11/20),72.5%(29/40),60%(12/20),57.5%(23/40),45%(9/20),70%(28/40),55%(11/20)。结论同一家庭内感染同类型致病菌株证实了HP的家庭内传播感染,进一步证实了HP的口-口传播途径。密切接触、饮食及生活习惯在HP致病菌的传播中有一定的作用。

Objective To investigate Helicobacter pylori （HP） intrafamilial infection and to analyze the genotype of HP. Methods Twenty families of HP positive were selected and 60 saliva samples of these family members were reexamined for HP by nested PCR. The genotypes of HP were distinguished by PCR directly. In this study, four pairs of genotype primers for HP were designed. Among them, the first pair was for cagA genotype; the second pair wass for vacAml genotype; the third pair was for vacAm2 genotype; and the last pair was for vacAsl genotype. The PCR products were detected in agarose gel electrophoresis and were photographed. The results were analyzed using Chi - Square Test and Fish＇ s Exact Test. Results The study showed that the four sets of primers could be used effectively for amplification of the targeted genes. Fourteen of 20 families were in concordance with the same genotype infection; only 6 families were infected with different type of genotype of HP. The genotypes infection rates of cagA, vacAml, vacAm2, and vacAsl for the adults were 45% （27/40） 55% （11/20）72.5% （29/40）and 60% （12/20）, respectively. The genotypes infection rates of cagA vacAml, vacAm2, and vacAsl for children were 57.5 % （23/40）, 45 % （9/20）, 70 % （28/40）, and 55 % （11/20）, respectively. The difference of both groups was no significant （ P 〉 0.05）. Conclusion The same genotypes of HP infection in one family confirm intrafamilial infection, which furtherly suggests Oral - Oral infectious route. Close touch, dietetic and life habit play important roles in HP transmission.